Computer programs typically utilize interfaces or call modules for accessing external modules for undertaking routine tasks. Such interfaces are customarily modified with system upgrades which utilize more modernized programming languages. Incorporating new interfaces requires system testing to ensure that the systems operate as intended and functionality would not be jeopardized when the new upgraded interfaces are incorporated into the operational system code. Testing, however, should be conducted in an efficient and effective manner off-line. Accordingly, there is a need to provide for a testing system which efficiently and effectively tests the new interfaces.